Hermetically encapsulated electronic devices for long term implantation generally use one or more coils being inductively coupled to external coils to either provide one or two-way communication with external devices and/or provide the power supply for the internal electronics (e.g. when the internal battery fails), or for recharging internal batteries. An example are cochlear implants.
Conventional cochlear implants either use ceramic cases or metal cases for the hermetic encapsulation of the electronics. When using ceramic packages, the coil can easily be placed within the package. For safety reasons metal packages are a better choice when employing internal rechargeable or non-rechargeable batteries. This requires the placement of the coil(s) outside the hermetic metal case. In present devices, this coil is connected to the case by a mechanically rigid construction, thus making the total implant rather clumsy and difficult to place, especially with small children.
Possible problems with a rigid connection that results in a fixed angle between the coil and the electronic housing include frequent movement in the area of interconnection through external pressure to the skin due to, for example, glasses, helmet, headphones, combs and/or pressure from overlying muscle tissue. Curvature changes in the skull as a child ages aggravates these problems, and can lead to wire breakages, skin breakdown over the implant, and fluid accumulation beneath the implant.